Road surface state estimation method and road surface state estimation device

Abstract

A device for estimating a state of a road surface on which a tire is running, the device including: an acceleration sensor 11 installed in the tire; an acceleration information acquiring means 12, 13, 14 that acquires acceleration information input to the tire from an output of the acceleration sensor 11 ; a storage means 15 that stores acceleration information of each road surface roughness set in advance; and a road surface state estimating means 16 that compares the acquired acceleration information with the acceleration information of each road surface roughness stored in the storage means 15 so as to estimate the state of the road surface.

The invention claimed is: 
     
       1. A method for estimating a state of a road surface on which a tire is running, the method comprising:
 a first step of acquiring acceleration information input to the tire by an acceleration sensor installed in the tire; 
 a second step of comparing the acquired acceleration information with acceleration information of each of a plurality of road surface roughnesses set in advance; and 
 a third step of estimating the state of the road surface from a comparison result. 
 
     
     
       2. The method for estimating a state of a road surface according to  claim 1 , wherein, the acceleration information acquired in the first step or the acceleration information compared in the second step is information of a pre-leading acceleration waveform out of the acceleration waveform detected by the acceleration sensor. 
     
     
       3. A device for estimating a state of a road surface on which a tire is running, the device comprising:
 an acceleration sensor installed in the tire; 
 an acceleration information acquiring means that acquires acceleration information input to the tire from an output of the acceleration sensor; 
 a storage means that stores acceleration information of each of a plurality of road surface roughnesses set in advance; and 
 a road surface state estimating means that compares the acquired acceleration information with the acceleration information of the each road surface roughness stored in the storage means so as to estimate the state of the road surface.